Guard for emery wheels and the like



Sept. 4, 1945. A. FLOHR ET AL GUARD FOR EMERY WHEELS AND THE LIKE Filed Feb. 16, 1944 Patented Sept. 4, 1945 Andrew Flohr and Alfred J. Flohr, Buffalo, N. Y.

6, 1944, Serial No. 522,598

7 Application February 1 7' Claims.

This invention relates to certain new and useful improvements in protective guards for grinding wheels and like rotating tools.

One of its objects is to provide a guard for tools 01 this character which is so designed and constructed as to adjustably cover or enshroud the operating side and peripheral portions of the tool while in use and thereby afford maximum protection to the operator at all times and in the event of breakage of the tool, cause an fragments thereof to be deflected away from him. A Another object is to provide a. guard for grinding wheels and the like having side sections disposed in overlying relation to the sides of the tool for adjustment toward and from the operating edge or periphery of the tool, and arcuate sections disposed over the periphery of the tool for adjustment circumferentiallytoward and from each other to expose more or less of the toolperiphery as gaged by the work being operated upon.

A further object of the invention is to provide a safety guard for emery or grinding wheels including a self-adjustable guard wall so mounted as to be displaceable by the work and transparent and shatterproof to enable the operator to observe the work being operated upon, and further so designed as to enable its application to precision grinders and at the same time prevent its marring or damaging the work brought-in contact therewith.

Other features of the invention reside in the construction and arrangement of parts hereinafter described and particularly pointed out in the appended claims.

In the accompanying drawing:

Figure 1 is a front end view of the guard constituting our invention. Figure 2 is a side elevation thereof, partly in section. Figure 3 is an enlarged fragmentary cross section taken on line 3-3, Figure 2. Figure 4 is a fragmentary front view of a modified form of the guard. Figure 5 is a similar view of another modification thereof. Figure 6 is a cross section taken on line 6-4;, Figure 5.

Similar characters of reference indicate corresponding parts throughout the several views.

By way of example, our invention has been shown in connection with a portable tool consisting of an emery wheel l0 attached to a shaft H extending through a tube I2 which serves as a handle for the manipulation of the tool by the operator. Disposed substantially over the upper half of the wheel to enclose the periphery and opposite sides thereof is a fixed guard section or hood I} having an attaching sleeve H projecting axially from the rear side thereof for detachable sliding engagement with the shaft-engagingtube ID. The front Wall l5 of this guard section is removable to permit the assembly of the latter over the wheel and the same may bessec red in place by screws I6 or like fastenings. ,This hood leaves the lower portion of the wheel exposed for operative engagement with the work but does not afiord complete protection to the operator, and should the wheel break while in use the wheelfragments will be obviously thrown out in any and all directions with thepossibility of serious injury to the operator. To guard against such a condition and insure maximum pmiection to the perator, we provide movable or displaceable guard means which are disposed over the exposed lower sides and periphery of the emery wheel and which may be set in given positions or be self-adjustable by contact With'the work and relative to the sides and periphery or the wheel so that at all times the wheel, with the exception of that portion thereof engaged by the work, is completely enshrouded and the possibility of inju y to the operator from flying fragments is reduced to a minimum. Y

As shown in Figures 1-3, inclusive, these guard means consist of displaceable side plates or walls I! which are mounted or'suspended on'the opposite sides of the fixed guard section I; and arcuateshaped plates or walls [8 suspended from the peripheral portion of such section. The side plates I! assume a position in' overlyingrelation to the sides-of the wheel revolving tool and their outer edgesar e of a contour concentric with the wheel and normally extend slightly beyond its periphery. Each side plate is suspended from the companion side wall of the fixed guard section by two sets of pivoted link means |'9,-20-to permit a universal displacement of the plate in a plane parallel to the wheel when the latter is brought in contact with the work to'expose the wheel foroperation on the work.- The upper links 19 are pivoted at their upper ends to a common central pivot 2| while the free ends of the lower links 20 are pivoted at 22 to the displaceable guard plate: I! at opposite sides of the wheel-axis. A spring i3'connected across .the two sets of links serves'to yieldingly resist inward displacement of the guard plate and tends normally to urge the same outwardly to a position slightly beyond the periphery of the emery wheel. A stop 24 projecting from the side wall of the guard section I3 below the pivot of the upper links I9 serves to limit the extensible movement of the two sets of links and the outward displacement of the guard wall 11. During its displaceable or full-floating movement, each guard plate I 1 is confined within a predetermined circumference and for this purpose its opposite side marginal edges are guided in offset lugs 25 formed on the guard section l3.

The arcuate-shaped guard plates 18 which extend over the exposed lower peripheral faces of the emery wheel may be adjustably set in a given position to expose any portion of the Wheel desired depending on the work being operated, or

. they may be yieldingly suspended to normallyi.':i

seek a contracted position to be spread apart by. contact with the work as it is presented into op-. 1

erative relation to the wheel. For this purpose each guard plate l8 contains a'longitudina'lslot l 26 through which a clamping screw 2] extends.

for adjusting the plate circumferentially about 7 the fixed guard section I 3.

Disposed between lugs'28-a'nd 29 projecting radially from the guard-section l3 and guard plate [8, respectively; is aspi ing 30; which, upon loos ening the clamping-screw 21, is adapted to urge By tightening the screw, the guard plate is held in a fixed position.

complete Shredding of the wheel not used *by the work and affords maximum protection to the operator againstflying fragments should the wheel become broken while in use.

In Figure 4, we have shown a modification of the side guard mounting, 32 indicatingthe guard plate ,Which'is suspended for radial movement irom the fixed guard section I3 by screw and slot connections 33, 34, whereby the plate can be adjusted in or. out and then' clamped in the position desired. i y I In precision" grinding, it is desired to observe the grinding operation'end at the same timepre vent marring' of the work by contact with other parts. 7 To thisen-d, we have shown injFigures 5 and 6 a guard plate'35 made of a transparent, shatterproof material, fsu'chas a plastic or the like, provided at'its periphery with equi-spaced anti-friction rollers 36.) V Wefclaim as ourinvention:

L A protective guard for rotating tools, comprising ahousing extending' part Way over the periphery and opposite sides of the tool, a movable guard wall mounted-on said housing in overlying relation to one of the exposed sides 'of the tool, means for connecting said guard wall with the housing to permit a'sliding-like displacement of the former relative to thelatter' in a plane parallel to that of the rotation of the tool, anda second guard wall adjustably mounted for circumferential movementon and constituting a continuation of the peripheral portion of said V V V v '2. A protective guard for rotating tools, comprising ahousing extending .part way over the periphery and opposite sides of the tool, and independently displaceable guard wallsapplied to the exposed side and peripheral portions of said housing and shiftab-le inwardly and circumferen- ';tool is brought into operative engagement therewith, and means operatively connecting said guard walls, respectively, with the companion side and peripheral portions of the housing and for guiding themduring displacement.

4. A protective guard for rotating tools, comprising a housing extending part way over the periphery and opposite sides of the tool, independently displaceable guard wall applied to the exposed side and peripheral -.porti0ns:of said housing and shiftable inwardly and circumferen tially, respectively, by contact with the work whenthe tool is .brought'into'ioperative engagement therewith, and means operatively connect ing said guard walls, respectively, with the companion side and peripheral portions of the housing and for guiding them during displacement; said means includingyieldable and stop elements for normallyurging the guard walls to predetermined positions in relation to, the 1 tool.

'5. A protective guard for rotating tools, comprising a substantially semi-circular. housingadapted to extend part way. over thesides'and periphery of the; tool, arcuateeshaped guards applied to the. periphery of-itheehousing and adapted to extend overythe-exposed periphery of the toolfor circumferentialdmovement toward and from each other to expose moreor lessof the tool as determined bythe work being operated upon, andmeans for adjustably connecting said guards to the housing includingscrew and slot connections and springs for normally urgin the guards opposite directions toward each otherupon releasing said connections. 5 I 6. A protective guard for rotatingtools, comprising a housing extending partway over the periphery and; oppositesides of; thflTtDOl', and a movable uard wall suspended from ;the housing, in overlying relatiomto one of the exposed sides of the tool for displacement in a plane parallel to the rotating tool and having means connected thereto for -yieldingly resisting its movement in any givenradially-inward direction; thev outer edge of said guard wall having-anti-efriction work: engaging elements gthereon. i 5

'7. A protective guard for rotatingitoolazcomprising a' housing extendingpart..way; over the periphery and opposite sides of thetool, and a movable'guard Wall suspended fromgthe housing in overlying relation to one of the exposed sides of the tool for displacementin a plane parallel to the rotating tool and having its outer edge sub-. stantially concentric with that, of the tool,..said' guard wall being made of shatter-proof glass and having anti-friction rollers in its peripheryior engagement with the work.. z, ;I 1

REWVIFLOHR. IALFREDJ. FLOHR..-.i 

